Various containers are in use to discharge the contents from the container, by squeezing the body of the container with fingers or by utilizing a pump fitted to the neck of the container.
There are laminated containers used to discharge the contents, and these containers comprise an outer layer and a peelably laminated inner layer. The inner layer of such a container breaks away from the outer layer and is deformed with the decrease in the contents. At that time, outside air is introduced into the void between the outer and inner layers.
However, in these containers of the laminated structure, in which the inner layer is peelable from the outer layer, the inner layer is deformed with the decrease in the volume of the contents. Because of this deformation, the deformed inner layer blocks the flow path and prevents the contents from being discharged. In addition, another problem is that the deformed inner layer gets less pressurized with the decrease in the contents even if the outer layer is squeezed hard, thus preventing smooth contents-discharging operation.
As a result that the smooth discharge operation is prevented, more contents are left unused, thus creating a problem that the contents cannot be utilized to the last drop.
The inside of some container remains at a reduced pressure after the inner layer has been deformed with the decrease in the contents. In that case, the outer layer fails to restore its original shape, thus creating another problem of bad outer appearance.
Still other problems come up if an air hole is formed to introduce outside air into the void between the outer and inner layers. Firstly, the production cost shows a steep rise because some changes in the design of the molding machine are required. Secondly, troublesome after-mold processes are required to shape the air hole. Since the number of processes has to be increased for the completion of the product, the production and processing become complicated.
This invention has been made to solve these problems found in conventional art. The technical problem of this invention is to create check valve mechanisms that are readily feasible in the containers of the laminated structure. Thus, the object of this invention is to provide a discharge container maintaining high productivity, showing good squeeze operation, and having improved outer appearance.